Sealing device

ABSTRACT

An apparatus  10  for sealing packages  20  is to be mounted as a part of a larger packaging machine, which fills packages  20  with products or substances, preferably food or beverages but could be any other suitable substance, then closes and seals the packages using the sealing apparatus  10  by folding each package transversally, thereby closing it and sealing the transversal fold, and subsequently delivers the packages to a final folding station.

TECHNICAL FIELD

The present invention relates to a sealing device or apparatus forsealing packages containing a product. The sealing apparatus is to bemounted as a part of a larger packaging machine, which fills packageswith products or substances, preferably food or beverages but could beany other suitable substance, then closes and seals the packages usingthe sealing apparatus by folding each package transversally, therebyclosing it and sealing the transversal fold, and subsequently deliversthe packages to a final folding station.

Moreover, the present invention also relates to a method using thesealing apparatus/device for sealing the packages.

PRIOR ART

In a packaging apparatus, such as an apparatus for packages containing afluid, preferably liquid or food of different kinds, it is of importancethat the transversal sealing of the package is leakproof. The sealing isperformed after folding of the package.

The sealing of the package depends on several parameters, e.g. the typeof packaging material used in the package, the thickness of thepackaging material etc, which in turn affects the folding of thetransversal joints to be sealed on the package.

This means that the folding of the transversal joint has to be done withsufficient or close tolerances, e.g. by aligning the folding and sealingequipment so that they correspond to each other and do not counteract,and/or by holding/supporting the package firmly during folding andsubsequent sealing so that the package is held in place and is formed orfolds as desired.

U.S. Pat. No. 4,546,592 discloses an apparatus for sealing a liquidpackage made of paper coated with plastic, the apparatus includes a pairof extending fingers for flattening the top edge of the package with thefolded seam strip. The fingers are insertable in the open end of thepackage and driven for an extending movement. The apparatus alsocomprises a pair of welding jaws fixed to pivoted levers. The fingersand their actuation means are mounted above the package.

A disadvantage with U.S. Pat. No. 4,546,592 is that wear of moving partsmay create a bigger risk of having material on the fingers and theiractuation means coming loose and falling down into the package before itis folded and sealed. Moreover, lubricants or any other contaminationsmay also fall into the open end of the package before sealing, therebycontaminating or polluting the package and any substance or productcontained in the package. This gives a lower quality concerning hygienicrequirements for the package and the apparatus.

Another problem is that the movable parts are difficult to disassembleor dismount from each other due to a complicated structure, whereby anymaintenance and cleaning of the sealing apparatus are difficult andtime-consuming creating a higher cost per package and/or product and ashorter working life for the apparatus.

SUMMARY OF THE INVENTION

The main objects of the present invention are to fold and seal packagesby using a novel sealing apparatus and a novel method of operating thesealing apparatus with a simpler, faster, more hygienic, and morereliable transversal folding and sealing of the packages.

These objects are achieved by an apparatus for sealing a package havingan open end, the apparatus comprising at least one pair of halves, whichare reciprocally movable between an open position and a closed sealingposition for sealingly closing the open end of the package. Theapparatus further comprises forming means comprising a pair of formingflaps, each forming flap being associated with a sealing half andpivotally attached at a first end to a support such that a second end ofeach forming flap is adapted to at least partly follow the reciprocalmovement of the associated sealing half, and in that the forming flapsduring the movement of the sealing halves towards the closed sealingposition press two opposing portions of the package towards each other.

Moreover, these objects are achieved by a method for sealing a package,which method uses the above-mentioned apparatus. The method comprisesthe steps of providing the apparatus with forming means comprising apair of forming flaps, setting the apparatus in a first openpackage-receiving position, supplying a package to the apparatus,associating each forming flap with a sealing half of at least one pairof reciprocally movable sealing halves, moving the at least one pair ofreciprocally movable sealing halves of the apparatus towards and intocontact with the package, pressing two opposing portions of the packagetowards each other by means of the pair of forming flaps during themovement of the at least one pair of reciprocally movable sealinghalves, biasing the at least one pair of sealing halves further bypressing against opposing portions of the package, thereby folding theopposing portions of the package, and sealing the package by supplyingenergy to the at least one pair of reciprocally movable sealing halves.

By providing a packaging apparatus with a sealing apparatus according tothe invention and operating the sealing apparatus by the suitableabove-mentioned method, the following main advantages are obtained: thefolding and sealing of each package are performed more accurately andeasier, thereby reducing adjustment time and giving increasedproductivity; cleaning of the sealing apparatus is performed easier,faster, and better, whereby the package and its content are keptsterilized creating a higher shelf-life for the package and itscontained substance; and, the sealing apparatus is easier to disassembleor dismount and maintain, thereby also giving increased productivity.

In a preferred embodiment each of the forming flaps is adapted to bepivoted from a first essentially vertical position to a second angledposition in which the second end is in contact with a portion adjacentthe open end of each package.

In another preferred embodiment of the above-mentioned apparatus theforming flaps is biased, such that it is kept in its first essentiallyvertical position when the sealing halves are in their open position.

In a further preferred embodiment the apparatus comprises at least threepairs of linkage arrangements including a first pair of linkagearrangements with two reciprocally movable halves provided with pressingmeans for pressing on opposing portions of the package at a distancefrom the open end thereof, a second pair of linkage arrangements withtwo reciprocally movable halves provided with forming means for formingeach package adjacent the open end thereof, and a third pair of linkagearrangements with two reciprocally movable halves provided with sealingmeans for closing and sealing the open end of each package.

Preferably, each of the forming flaps is attached at its first end toone end of each half of the second pair of linkage arrangements betweenthe third pair of linkage arrangements and the second pair of linkagearrangements.

Preferably, the forming flaps is biased by means of a spring, which isoperatively connected to the first end of each of the forming flaps.

In a preferred embodiment each of the forming flaps is attached at itsfirst end to an upper side of each half of the second pair of linkagearrangements.

Preferably, each of the forming flaps is generally T-shaped and orientedsuch that the second end of the flap forms the overhead horizontal legof the T.

In a preferred embodiment the three pairs of linkage arrangements forsealingly closing the open end of each package are vertically spacedapart, so that the movable halves of the linkage arrangements are freelymovable in relation to each other during sealing and closing of eachpackage.

In a further embodiment the third pair of linkage arrangements with twohalves provided with sealing means for sealingly closing the open end ofeach package is placed at a vertical distance from each half of thesecond pair of linkage arrangements, which vertical distance is adaptedso that the flap is pivoted by the two halves of the third pair oflinkage arrangements from its first essentially vertical position to itssecond angled position for pressing two opposing portions of the packagetowards each other.

In yet a further embodiment the first pair of linkage arrangements isconnected to a first carrier movably provided on a guide, the secondpair of linkage arrangements is connected to a second carrier movablyprovided on said guide, the third pair of linkage arrangements isconnected to a third carrier movably provided on said guide, and thecarriers are connected to a cam curve disc.

In yet an additional embodiment each half of the first pair of linkagearrangements comprises an arm which in a first end is provided with thepressing means for pressing on a portion of the package at a distancefrom the open end thereof and which in a second end is pivotablyconnected to the first carrier by a link, and which between the firstand second ends is provided with a fixed pivot point.

In a further embodiment each half of the second pair of linkagearrangements comprises a first and a second arm, which first and secondarms being connected to each other in first ends thereof and providedwith the forming means for forming each package adjacent the open endthereof, which first arm in a second end is pivotably connected to thesecond carrier by a link and which between the first and second ends isprovided with a fixed pivot point, and which second arm in a second endis fixed and which in between the first and second ends is provided witha fixed pivot point. This geometry of the second linkage arrangementsgive rise to a “wave”-like motion of the forming means when they aremoved towards and from the package, i.e. the the ends of the linkagearrangements which are provided with the forming means will make atilting motion during the movement. The tilting is accomplished in thatthe first end of the first arm during a part of the movement moves to aposition which is lower than the position of the first end of the secondarm, seen in relation to the package fin created during sealing. Thetiliting motion takes place in the end of the movement towards thepackage and in the beginning of the movement from the package. This“wave”-like motion of the forming means is advantageous in that itminimises the risk of damaging a portion of the package near the seal,i.e. near the fin, for example the triangular corner flaps present inmany known carton packages. This is especially useful when the formingmeans are moved from the package since the package has then been sealedand is less flexible due to the rigid fin.

In yet a further embodiment each half of the third pair of linkagearrangements comprises an arm which in a first end is provided with thesealing means for closing and sealing the open end of each package andwhich in a second end is pivotably connected to the third carrier by alink, and which between the first and second end is provided with afixed pivot point.

Preferably, the third carrier is connected to the cam curve disc via afourth carrier. The fourth carrier is connected to the third carrier viaan actuation member, which actuation member is adapted to change themutual distance between the third and fourth carriers along the guidefor biasing the sealing means for closing and sealing the open end ofeach package. By providing an actuation member an additional sealingforce is obtained which further secures the creation of a satisfactoryseal.

Preferably, the fixed pivot point of the first arm is arrangedsubstantially at the same distance from the forming means in a verticaldirection as the fixed second end of the second arm, so that thepivotable portion of the first arm is longer than the pivotable portionof the second arm.

Advantageously, the fixed pivot point of the arm of each half of thefirst linkage arrangements and the fixed pivot point of the arm of eachhalf of the third linkage arrangement are arranged substantially at thefixed pivot point of the first arm and the fixed second end of thesecond arm of each half of the second linkage arrangements in thevertical direction. By providing an apparatus with the above-mentionedfeatures further advantages, in addition to the above-mentionedadvantages, are obtained. The carriers and the cam curve, being thedrive equipment, can be separated from the sealing equipment by forexample a middle section. By providing the above-mentioned substantially“coinciding” points (fixed point, pivot points etc) in or near themiddle section only few pivot points will be present in the area nearthe package. Thus, the risk of disturbing the air flows provided to keepthe package and its content sterilized is minimized and any dirt fromthe drive equipment can be shielded from the area near the package. Thisis an advantage when the package content is exceptionally sensitive.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described in more detail withreference to the enclosed drawings, in which:

FIG. 1 schematically shows a general assembly of an apparatus accordingto a first embodiment of the invention to be mounted in a packagingmachine (not shown),

FIG. 2 schematically shows an assembly of linkage arrangements in anapparatus according to a second embodiment of the invention in an opwnpackage-receiving position,

FIG. 3 schematically shows a first pair of linkage arrangementsaccording to the embodiment shown in FIG. 2,

FIG. 4 schematically shows a second pair of linkage arrangementsaccording to the embodiment shown in FIG. 2,

FIG. 5 schematically shows a third pair of linkage arrangementsaccording to the embodiment shown in FIG. 2,

FIG. 6 schematically shows a first pair of linkage arrangementsaccording to the first embodiment shown in FIG. 1,

FIG. 7 schematically shows a second pair of linkage arrangementsaccording to the first embodiment shown in FIG. 1,

FIG. 8 schematically shows a third pair of linkage arrangementsaccording to the first embodiment shown in FIG. 1,

FIG. 9 schematically shows a view of a pivotable T-shaped devicefacilitating the sealing of packages from a first angle,

FIG. 10 schematically shows a view of the pivotable T-shaped device inFIG. 6 from a second angle, and

FIG. 11 schematically shows a plan view of the pivotable T-shaped devicein FIGS. 6 and 7 from another angle.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows an apparatus 10 for sealing packages 20 (not shown)according to a first embodiment of the present invention. This apparatus10 is to be mounted as a part of a larger packaging machine (not shown),which fills packages 20 with products or substances, preferably food orbeverages but could be any other suitable substance, then closes andseals the packages using the sealing apparatus 10 by folding an open end20 a of each package, thereby closing the open end and sealing the fold,and subsequently delivers the packages to a final folding station (notshown). The packages are transported into the sealing apparatus 10 fromleft to right in FIG. 1 and out of the sealing apparatus after beingsealed according to the three arrows in FIG. 1, two arrows to the leftin FIG. 1 and one arrow to the right in FIG. 1. The large packagingmachine and its function will not be explained in more detail in thisdescription because its function and structure is common knowledge for askilled person.

Each of the packages 20 are handled upside down and transported into thesealing apparatus 10, each package has its first open bottom end 20 a,see FIG. 9, pointing upwards in the vertical direction and a second topend (not shown) pointing downwards in the vertical direction.

FIG. 1 illustrates a general assembly of a first embodiment of theinvention showing all the parts, equipments and arrangements requiredfor the operation of the sealing apparatus 10 except for the meansrequired for connecting and fastening the sealing apparatus to the largepackaging machine (not shown).

The sealing apparatus 10 shown in FIG. 1 comprises two primary sections,a first upper section 30 with an equipment for sealing the packages 20and a second lower section 40 with a driving or operation equipment foroperating or actuating, i.e. move the sealing equipment. The uppersection 30 and the lower section 40 are separated by a middle section 50of a frame 70 forming a partition.

The object of the middle section 50 separating the sealing equipmentfrom the drive equipment is to ensure that the packages 20, and, morespecifically, the open end 20 a of each package and the content, i.e.the air and substance or fluid contained in the package, are kept clean,hygienic, and sterilized by not being exposed to any contaminationscreated by the drive equipment, e.g. lubricants, dust, dirt, or evensolid particles created by wear between the moving parts of the driveequipment, which particles otherwise could end up in the packages bybeing transported, in this case, first upwards and then into thepackages (not shown).

The packages 20 are kept hygienic and sterilized by supplying a sterileair flow constantly downwards from the top of the sealing apparatus 10in FIG. 1 through the apparatus and out adjacent the middle section 50,so that any contaminations are kept away from each package and its openend 20 a and urged out with the sterile air flow out of the sealingapparatus, this is also facilitated by the structure of the sealingapparatus because all of the lubricants and most of the moving metalparts are placed below the packages 20, or more specifically under themiddle section 50 of the frame 70.

The sealing apparatus 10 seals at least two packages 20 at a time whenoperating in this embodiment and therefore the upper sealing equipmentshown in FIG. 1 uses two pairs of sealing devices 80 each pair havingtwo movable mirror-inverted arrangements 100 and 110 in the form of linksystems. This adds up to two link systems 100 to the right in FIG. 1 andtwo link systems 110 to the left in FIG. 1. Here, in FIG. 1, only onehalf 100 of the two movable mirror-inverted link systems 100 and 110 inthe nearest sealing device pair 80 is shown in its entirety to the rightfor clarity reasons. The other nearest link system half 110 to the leftis only partly shown, i.e. only the parts directly engaging each package20 (not shown) are shown. Each pair of sealing devices 80 is attached tothe frame 70, the nearest pair in FIG. 1 is attached at one side of theframe and is more clearly seen, the other pair is attached on the otherside of the frame 70. It should be understood that the pair of sealingdevices 80 beyond the first pair operates and is actuated andconstructed in the same manner as the first nearest pair of the sealingdevices 80 and will therefore not be explained in detail.

Each of the four link systems 100 and 110 being partly and/or entirelyshown in FIG. 1 has three pairs of armlike or leglike linkagearrangements. In the following, these linkage arrangements will first bedescribed according to a second embodiment of the invention, whichsecond embodiment is substantially similar to the first embodimentexcept for the design of the linkage arrangements and the driveequipment.

FIG. 2 shows an assembly of the three linkage arrangements and FIG. 3-5show them separately. Each of these pairs of linkage arrangements hasdifferent functions. The first pair of linkage arrangements, denoted 120and shown in FIG. 3, is provided with pressing means 121 for pressing onopposing portions of the package 20 at a distance from the open end 20 athereof and will hereinafter be referred to as a headspace device. Thefunction of the headspace device 120 is to control the filled volume inthe headspace of each package 20. The second pair of linkagearrangements, denoted 130 and seen in FIG. 4, is provided with formingmeans 131 for forming each package adjacent the open end 20 a thereof,and will hereinafter be referred to as a forming tool. The third pair oflinkage arrangements, denoted 140 and shown in FIG. 5, is provided withsealing means 141 for closing and sealing the open end 20 a of eachpackage 20.

The first pair of linkage arrangements 120, i.e. the head space device120 comprises two halves both shown in FIG. 3, a first right head spacehalf 150 and a first left head space half 160 for controlling the filledvolume in the headspace of each package 20 by pressing each package 20at a distance from the open end 20 a. The two halves 150, 160 are placedopposite each other and the only difference between the two halves arethat the left half 160 is mirror-inverted in relation to its oppositeright half 150. When describing the head space device only the righthalf will be described. The right first head space half 150 of the headspace device 120 comprises a package engaging member 122.

The second pair of linkage arrangements 130, i.e. the forming tool, isshown in FIG. 4 and comprises a first right forming tool half 170 and afirst left forming tool half 180, the first left forming tool half 180of the forming tool 130 is placed opposite the first right forming toolhalf 170 and the only difference between the two opposite halves 170,180 is that the left half 180 is mirror-inverted in relation to itsopposite right half 170. When describing the forming tool only the righthalf will be described. The right first forming tool half 170 of theforming tool 130 comprises first and second package engaging members132, 133. The function of the forming tool 130 and these packageengaging members 132, 133 will be described in detail later in thisdescription.

The third pair of linkage arrangements 140 is shown in FIG. 5 andcomprises a first right sealing jaw half 190 and a first left sealingjaw half 200, which are placed opposite each other. The right firstsealing jaw half 190 of 35 the sealing jaw 140 comprises a packageengaging member 142 for sealing the package 20. There is a functionaland structural difference between the two sealing jaw halves 190 and200, the difference being that only the first right half 190 activelyperforms the sealing of each package 20, while, at the same time, theother opposite first left half 200 only works as an anvil during thesealing procedure. This means that the right half 190 is provided withthe active sealing means 141 and the opposite left half 200 basicallyhas a shape corresponding to the other right half 190 for ensuring asecure sealing. In this embodiment the sealing method is inductionsealing where a radio frequency alternating current is supplied andcauses induced currents in a aluminium foil provided in each multi-layerpackage 20, thereby heating the aluminium foil, which in turn heats aplastic layer in the multi-layer package. Induction sealing iswell-known and will not be described in more detail.

Each of the pairs of linkage arrangements 120, 130, and 140 is incommunication with, or, more specifically, connected to the driveequipment in the lower section 40 of the apparatus 10 for moving thelinkage arrangements 120, 130, and 140 in relation to each other, thesealing apparatus 10 as a whole, and the packages 20 to be sealed. Onlythe features of the drive equipment that are essential for theunderstanding of the invention will be described. The drive equipment,see FIG. 2, comprises a cam curve disc 220. An electric motor 221 isconnected to a transmission/gear box which in turn drives the cam curvedisc 220. Further, the drive equipment comprises a guide 230, preferablyin the form of a linear shaft. Said guide 230 is fixed to the middlesection 50 of the frame 70 and is provided with a first and a secondcarrier 240, 250 which is each movably arranged thereon. The guide 230is further provided with a third and a fourth carrier 260, 270 which areconnected to each other via a frame 262 and together movably arranged onthe guide 230. The first pair of linkage arrangements 120 is connectedto the first carrier 240, the second pair of linkage arrangements 130 isconnected to the second carrier 250 and the third pair of linkagearrangements 140 is connected to the pair comprising the third carrier260 and the fourth carrier 270.

The first, second and fourth carriers 240, 250, 270 each has thefunction of a cam and each of the first and second carriers is fittedinto an associated cam curve (partly shown) in the cam curve disc 220,whereas the fourth carrier 270 is in contact with and follows the outerperiphery of the cam curve disc 220 by a roll (not shown). Said roll isheld biased by a spring 263 connected to the third carrier 260. Each ofthe carriers 240, 250 and the pair of carriers 260, 270 are movedrelatively each other by rotating the cam curve disc 220 using theelectric motor 221 and the transmission box. Upon rotation of the camcurve disc 220 the first, second and fourth carriers 240, 250, 270 willmove upwards and downwards along the linear guide 230, in a verticaldirection in FIG. 2. Since the third carrier 260 is connected to thefourth carrier 270 it will move uniformly. This will not be described infurther detail, since the use and function of a cam curve disc andcarriers moving by means of such a cam curve disc is common knowledgefor a skilled person.

The second carrier 250 is located at the top of the four carriers, seeFIG. 2, the first carrier 240 is located below the second carrier 250,the third carrier 260 is located below the first carrier 240 and thefourth carrier 270 is located at the bottom, i.e. below the thirdcarrier 260.

If the first or the second carrier 240, 250 is moved upwards in FIG. 2,each associated package engaging part of the head space device 120 orthe forming tool 130 is moved into contact/engagement with the package20 to be sealed, and if the first or the second carrier 240, 250 ismoved downwards to the position shown in the figures, each associatedpackage engaging part of the head space device 120 or the forming tool130 is moved away from the package 20. If the fourth carrier 270 ismoved downwards, thereby moving also the third carrier 260 (which actsas a slave) downwards, each associated package engaging part of thesealing jaws 140 is moved into contact/engagement with the package 20 tobe sealed, and if the fourth carrier 270 is moved upwards to theposition shown in FIG. 2 or 5, thereby moving the third carrier 260upwards, each associated package engaging part of the sealing jaws 140is moved away from the package 20. How this is accomplished will now bedescribed.

Each half 150, 160 of the first pair of linkage arrangements 120comprises an arm 123, see FIG. 3. The pressing means 121, with thepackage engaging member 122, for pressing on a portion of the package20, is arranged to an upper, first end 123 a of the arm 123. Preferably,the package engaging member 122 is pivotably arranged to be able tosmoothly press on the package 20. A lower, second end 123 b of the arm123 is pivotably connected to the first carrier 240 by a link 241.Between the first and second ends 123 a, 123 b a fixed pivot point 123 cis provided (not shown, but marked with a dot in the figure). The pivotpoint 123 c connects the arm 123 to the frame 70 and in this embodimentthe pivot point 123 c is located at the middle section 50 so that it isshielded from the package area by for example bellows.

Each half 170,180 of the second pair of linkage arrangements 130comprises a first and a second arm 134, 135, see FIG. 4. Each arm 134,135 has a first end 134 a, 135 a and these two respective first ends 134a, 135 a are fixedly connected to each other by a link 136 to which theforming means 131 with the first and second package engaging members132,133 are arranged. A second end 134 b of the first arm is pivotablyconnected to the second carrier 250 by a link 251. Further, there isprovided a fixed pivot point 134 c (not shown, but marked with a dot inthe figure) between the first and second ends 134 a, 134 b of the firstarm 134. The pivot point 134 c connects said first arm 134 to the frame70 and in this embodiment the pivot point 134 c is located at the middlesection 50 so that it is shielded from the package area by for examplebellows. A second end 135 b of the second arm 135 is fixed. Preferably,it is fixed to the middle section 50. However, a fixed pivot point 135 cis provided in between the first and second ends 135 a, 135 b of thesecond arm 135. Thus, the upper portion of the second arm 135 ispivotable. As can be seen in the figure the first and second arms 134,135 of each half of the second linkage arrangements 130 are arranged soin relation to each other that the fixed pivot point 134 c of the firstarm 134 is arranged substantially at the same distance from the formingmeans 131 in a vertical direction as the fixed second end 135 b of thesecond arm 135. Thus, the pivotable portion of the first arm 134 islonger than the pivotable portion of the second arm 135. As can beunderstood from FIG. 4, the geometry of the second linkage arrangements130 give rise to a “wave”-like movement of the forming means 131 whenthey are moved towards and from the package 20 (not shown in FIG. 4).This will be described in more detail further on.

Each half of the third pair of linkage arrangements 140 comprises an arm143 which in a first end 143 a is provided with the sealing means 141for closing and sealing the open end of each package 20, see FIG. 5. Asecond end 143 b of said arm 143 is pivotably connected to the thirdcarrier 260 by a link 261. Further, the arm 143 is provided with a fixedpivot point 143 c (not shown, but marked with a dot in the figure)between the first and second end 143 a, 143 b. The pivot point 143 cconnects the arm 143 to the frame 70 and in this embodiment the pivotpoint 143 c is located at the middle section 50 so that it is shieldedfrom the package area by for example bellows.

As can be seen in the figures the fixed pivot point 123 c of the arm 123of each half of the first linkage arrangements 120 and the fixed pivotpoint 143 c of the arm 143 of each half of the third linkage arrangement140 are arranged substantially at the fixed pivot point 134 c of thefirst arm 134 and the fixed second end 135 b of the second arm 135 ofeach half of the second linkage arrangements 130 in the verticaldirection.

Advantageously, each of the total of four arms 123, 134,135, 143 is madeof metal, preferably, alloy steel that fulfills the hygienicrequirements of the present invention, e.g. a sufficient durabilityagainst cleaning detergents, acids and bases.

The above described linkage arrangements 120,130, 140 can havealternative designs and one such alternative design is shown in thesecond embodiment of the invention and can be seen in FIG. 6-8. Whendescribing the linkage arrangements 120, 130,140 of the secondembodiment similar features will be denoted with the same referencenumerals. The linkage mechanisms are here located in the upper section30 of the apparatus 10 and actuated by tie rods. The package engagingmember 122 of the head space device 120, see FIG. 6, is actuated by atie rod 124 which is connected to a parallelogram linkage system 125.The linkage arrangements of the forming tool 130 and the sealing jaw 140are designed in similar ways and can be seen in FIGS. 7 and 8respectively. For the sealing jaws 140 two tie rods are used.

In the following, and with reference to FIGS. 9-11, the first and secondpackage engaging members 132, 133 of the forming means 131 will bedescribed. The first package engaging member 132 has the form of aU-shaped grip member that is adapted to grasp each package 20 from theopposite side in relation to the other corresponding opposite firstpackage-engaging member. The second package engaging member 133 is aforming flap. The forming flap 133 is a T-shaped (wing like) device, andsince it is very similar to a flap for facilitating the forming andfolding of each package 20 it is denoted as a forming flap. Here, onlyone wing like device or forming flap 133 is illustrated and rotatablyattached with a first end 133 a, the vertical member, i.e. the verticalleg of the T, to each of the two forming tool halves 170 and 180. Oneforming flap 133 is attached against one end, i.e. an upper side of thefirst right forming tool half 170 and one forming flap 133 is attachedagainst an upper side of the first left forming tool half 180 (notshown). The second end 133 b of the T-shaped flap 133 is the overheadhorizontal leg of the T. The function of this pair of forming flaps 133will only be explained with reference to one device because the otherworks and moves in a similar mirror-inverted way.

The forming flaps 133, in the vertical direction, as seen in FIG. 2, areplaced between the third pair of linkage arrangements, i.e. the sealingjaw 140, and the second pair of linkage arrangements, i.e. the formingtool 130. The reason for this is to ensure that the movable halves 150,160,170,180, 190, 200 of the linkage arrangements, i.e. the head spacedevice 120, the forming tool 130, and the sealing jaw 140 are freelymovable in relation to each other during sealing and closing of eachpackage 20.

The forming flap 133 shown in FIGS. 9-11 is slightly biased, in thenon-operating or non-sealing state, i.e. when the sealing jaws 190, 200is in a first open position, in an essentially vertical directionupwards, by means of a wing pin 137 protruding through attachment holes138 in each upper side of the forming tool halves 170 and 180, and beingprovided with resilient biasing means in the form of at least one spring139, e.g. a helical spring or a plate spring. The forming flap 133 isadapted to be rotated, or, more specifically, pivoted from a firstessentially vertical position (not shown) into a second angled positionwith the second end 133 b in contact with a portion of each package 20,i.e. when the sealing jaws 190, 200 is in a second closed position forsealingly closing each package 20.

The three pairs of linkage arrangements 120, 130,140 shown in FIG. 2 forsealing each package 20 are placed on a vertical distance from eachother so that the moving parts, i.e. the movable halves 150, 160,170,180,190, 200 in the pairs, do not collide when moved duringoperation of the sealing apparatus 10.

The third pair of linkage arrangements 140, i.e. the sealing jaw, withthe two halves 190, 200 for sealing each package 20 is placed on avertical distance from the upper side 170 a, 180 a of each half 170,180of the second pair of linkage arrangements 130, i.e. the forming tool,which vertical distance is adapted so that the forming flap 133 is movedby the two halves 190, 200 contacting/engaging the flap 133 from itsfirst essentially vertical position into its second angled position bybeing rotated towards and into contact with the package 20 to be sealed.This means that the wing like flap 133 on either of the two forming toolhalves 170 or 180 is pushed from its first essentially vertical position(not shown) from the left in FIG. 11 to the right towards the package20, the same goes for the opposite placed wing like flap on the oppositeforming tool half 170 or 180. The rotation of the flap 133 into contactwith the open end 20 a of the package 20 means that the flap 133 pressesat two opposing sides of the package 20 towards each other because theforming tool 130 grips/holds the package adjacent its open end 20 a. Theflap 133 is placed between the sealing jaws 140 and the forming tool130.

The fourth carrier 270 is connected to the frame 262 by an actuationmember 272 which in this example is a cylinder, preferably a pneumaticcylinder, see FIG. 2. The function of this cylinder 272 is to move thethird carrier 260 along the linear guide 230 to provide an additionalbiasing of the two sealing jaw halves 190 and 200 against each otherduring the sealing moment. Thereby, some of the sealing force will beprovided by the cam curve disc 220, although most of the sealing forcewill be provided by the cylinder 272 so that the sealing of atransversal joint at the bottom of each package 20 is ensured in asufficient way. This procedure/function will be explained in more detaillater in this description.

Now, the function of the sealing apparatus 10, a method of operating itaccording to the invention and the operation and movements of thesealing devices 80 will be explained in more detail. All of the sealingdevices 80, i.e. the operation and movements of the two pairs of headspace devices 120, the two pairs of forming tools 130, and the two pairsof sealing jaws 140 and their associated two halves 150, 160, 170, 180,190, 200 will be explained with reference to only one pair of head spacedevices 120, forming tools 130, and sealing jaws 140.

The sealing apparatus 10 has a first primary position, i.e. a startingposition or an open position, see FIG. 2, which is a standby state forthe sealing apparatus 10 just before a package 20 enters the sealingapparatus 10, and a second primary position, i.e. a final position forsealing and closing the package. The second position is not shown. Theopen position is defined in the following way: the sealing jaw 140 isopen, i.e. the two sealing jaw halves 190, 200 are positioned in theirposition farthest from each other. This also means that the head spacedevice 120 and the forming tool 130 and their halves 150, 160, 170, 180,respectively, are in corresponding positions in relation to each other,and that the first and second carriers 240, 250 also are in their lowestpositions in relation to the figure. The links 241 and 251 are therebydirected sligthly upwards. The fourth carrier 270, and thereby the thirdcarrier 260, are in their highest positions in relation to the figure.The link 261 is thereby directed sligthly downwards.

In this open first primary position for the sealing apparatus 10, apackage 20 is supplied into the sealing apparatus. The forming tool 130with its two halves 170, 180 firstly grips or grasps the package 20 fromopposite, i.e. opposing sides or portions by the second carrier 250being pushed upwards, in relation to FIG. 2, along the linear guide 230by the associated cam curve for the forming tool 130 in the cam curvedisc 220. At the same time, the head space device 120 with its twohalves 150,160 moves towards the package 20 from opposite sides orportions, and, instanteously makes a stop when touching the package 20,and, then, starts pressing against the package 20 for adjusting thevolume contained in the package 20. The movement or pivoting of the headspace device 120 is done in the similar way as for the forming tool 130by the first carrier 240 being pushed upwards, in relation to FIG. 2,along the linear guide 230 by the associated cam curve for the headspace device 120 in the cam curve disc 220. Then, the sealing jaw 140with its two opposite placed sealing halves or jaws 190, 200 isactuated, the halves are also placed opposite each other. The movementor pivoting of the sealing jaw 140 is done in the essentially similarway as for the head space device 120 and the forming tool 130, the maindifference is that the third linkage arrangements 140 are actuated bytwo different means. Firstly, the fourth carrier 270, and thereby alsothe third carrier 260, are being retracted or pulled downwards, inrelation to FIG. 2, along the linear guide 230 by the associated camcurve, which in this case is the outer periphery of the cam curve disc220. The two sealing jaw halves 190 and 200 are thereby pivoted/movedtowards each other and comes into contact with a portion of thevertically pointing second end 133 b shown in FIGS. 9-11 of the formingflaps 133. When the associated sealing jaw half 190 or 200 passes overthe forming flap 133 it pushes the associated forming flap 133 towardsthe package 20, i.e the forming flap 133 partly follows the sealing jaw140. The second ends 133 b of the forming flaps 133 and the packageengaging members 141 of the associated sealing jaw 140 come into contactwith opposing portions or sides of the package 20 andsupports/facilitates the folding and forming of the open end 20 a of thepackage 20 during forming and sealing into a closed end. Secondly, thepneumatic cylinder 272 connected to the fourth carrier 270 and the frame262 provides an additional biasing or pressing of the sealing jaws 140towards each other. Since the fourth carrier 270 is biased towards thecam curve disc 220, the cylinder 272 presses the frame 262 downwards.This causes the third carrier 260 to move a small additional distancealong the linear guide 230 in a direction downwards. Thereby, the mutualdistance between the third and fourth carriers 260, 270 along the guide230 is changed. Also, this creates a gap, corresponding to theadditional distance, at line A in FIG. 5. A sealing force is therebyprovided and the sealing can be performed. The additional pressing ofthe sealing jaw halves 190 and 200 a small distance by means of thecylinder 272 facilitates the sealing of the transversal seal.

The movement of the head space device 120 with its two halves 150, 160are done in a way that the pressing of the package 20 has begun beforethe sealing halves or jaws 190, 200 comes in contact with the package20. The movement of the head space device 120 with its two halves150,160 are done in a way that the pressing of the package 20 isfinished before the movement of the sealing halves or jaws 190, 200 isstopped.

When the sealing is completed, the sealing jaw 140, the forming tool130, and the head space device 120 are reversed and moved/rotated awayfrom the package 20. Then, or, more specifically, by partly followingthe reversed movement of the sealing jaw 140, the forming flaps 133 arebiased/moved by the spring 139 back to its first essentially verticalposition in the standby state or open position for the sealing apparatus10, which then is ready to receive another new package 20 for anothersealing procedure.

As can be understood from the geometry of the second linkagearrangements 130 the forming means makes a “wave”-like motion when theyare moved towards and from the package 20. The link 136 connecting therespective first ends 134 a, 135 a of the first and second arms 134, 135and to which the forming means are provided makes a tilting motionduring part of the movement. The tilting is accomplished in that thefirst end 134 a of the first arm 134 during part of the movement isplaced in a position which is lower than the position of the first end135 a of the second arm 135, in relation to the package fin createdduring sealing. The tiliting motion takes place in the end of themovement towards the package 20 and in the beginning of the movementfrom the package 20. Thus, when the forming tool 130 is moved away fromthe package 20 it will not touch it.

Although the present invention has been described with respect topreferred embodiments, it is to be understood that various modificationsand changes to the invention may be made without departing from theobject and scope of the present invention as defined in the appendedclaims.

In the embodiments described induction sealing is used. Alternatively,the sealing may also be a so-called ultrasonic sealing, where aultrasonic oscillation is applied to the packaging material in thepackage to be sealed such that the hysteresis heats the interfacebetween the materials to be sealed together. Moreover, the sealing couldalso be a so-called impulse heating where a hot baris put inabutment/contact with the packaging material such that a plasticmaterial in the interface temporarily at least partly melts and thensolidifies creating the sealing. These above-mentioned ways of sealingpackages are well-known and will not be explained in more detail.

The sealing apparatus 10 in the embodiments described seals at least twopackages 20 at a time but it could of course be sealing more or lessthan two depending on the production requirements and the availablespace for the sealing apparatus, whereby only one pair of sealingdevices 80 would reduce the size of the apparatus and theproduction/sealing rate, and more than two pairs of sealing devices 80would increase the size of the apparatus and the production/sealingrate, as is readily understood by a skilled person.

1. A apparatus for sealing a package having an open end, the apparatus comprising at least one pair of halves, which are reciprocally movable between an open position and a closed sealing position for sealingly closing the open end of the package, wherein the apparatus further comprises forming means comprising a pair of forming flaps, each forming flap being associated with a sealing half and pivotally attached at a first end to a support such that a second end of each forming flap is adapted to at least partly follow the reciprocal movement of the associated sealing half, and in that the forming flaps during the movement of the sealing halves, towards the closed sealing position press two opposing portions of the package towards each other.
 2. An apparatus according to claim 1, wherein each of the forming flaps is adapted to be pivoted from a first essentially vertical position to a second angled position in which the second end is in contact with a portion adjacent the open end of each package.
 3. An apparatus according to claim 2, wherein each of the forming flaps is biased, such that it is kept in its first essentially vertical position when the sealing halves are in their open position.
 4. An apparatus according to claim 1, wherein the apparatus comprises at least three pairs of linkage arrangements including a first pair of linkage arrangements with two reciprocally movable halves, provided with pressing means for pressing on opposing portions of the package at a distance from the open end thereof, a second pair of linkage arrangements with two reciprocally movable halves provided with forming means for forming each package adjacent the open end thereof, and a third pair of linkage arrangements with two reciprocally movable halves provided with sealing means for closing and sealing the open end of each package.
 5. An apparatus according to claim 4, wherein each of the forming flaps is attached at its first end to one end of each half of the second pair of linkage arrangements between the third pair of linkage arrangements and the second pair of linkage arrangements.
 6. An apparatus according to claim 3, wherein each of the forming flaps is biased by means of a spring, which is operatively connected to the first end of each of the forming flaps.
 7. An apparatus according to claim 5, wherein each of the forming flaps is attached at its first end to an upper side of each half of the second pair of linkage arrangements.
 8. An apparatus according to claim 1, wherein each of the forming flaps is generally T-shaped and oriented such that the second end of the flap forms the overhead horizontal leg of the T.
 9. An apparatus according to claim 4, wherein the three pairs of linkage arrangements for sealingly closing the open end of each package are vertically spaced apart, so that the movable halves of the linkage arrangements are freely movable in relation to each other during sealing and closing of each package.
 10. An apparatus according to claim 9, wherein the third pair of linkage arrangements with two halves provided with sealing means for sealingly closing the open end of each package is placed at a vertical distance from each half of the second pair of linkage arrangements, which vertical distance is adapted so that the flap is pivoted by the two halves of the third pair of linkage arrangements from its first essentially vertical position to its second angled position for pressing two opposing portions of the package towards each other.
 11. An apparatus according to claim 4, wherein the first pair of linkage arrangements is connected to a first carrier movably provided on a guide, the second pair of linkage arrangements is connected to a second carrier movably provided on said guide, the third pair of linkage arrangements is connected to a third carrier movably provided on said guide, and the carriers are connected to a cam curve disc.
 12. An apparatus according to claim 11, wherein each half of the first pair of linkage arrangements comprises an arm which in a first end is provided with the pressing means for pressing on a portion of the at a distance from the open end thereof and which in a second end is pivotably connected to the first carrier by a link, and which between the first and second ends is provided with a fixed pivot point.
 13. An apparatus according to claim 11, wherein each half of the second pair of linkage arrangements comprises a first and a second arm, which first and second arms being connected to each other in first ends thereof and provided with the forming means for forming each package adjacent the open end thereof, which first arm in a second end is pivotably connected to the second carrier by a link and which between the first and second ends is provided with a fixed pivot point, and which second arm in a second end is fixed and which in between the first and second ends is provided with a fixed pivot point.
 14. An apparatus according to claim 11, wherein each half of the third pair of linkage arrangements comprises an arm which in a first end is provided with the sealing means for closing and sealing the open end of each package and which in a second end is pivotably connected to the third carrier by a link, and which between the first and second ends is provided with a fixed pivot point.
 15. An apparatus according to claim 11, wherein the third carrier is connected to the cam curve disc via a fourth carrier.
 16. An apparatus according to claim 15, wherein the fourth carrier is connected to the third carrier via an actuation member, which actuation member is adapted to change the mutual distance between the third and fourth carriers along the guide for biasing the sealing means for closing and sealing the open end of each package.
 17. An apparatus according to claim 13, wherein the fixed pivot point of the first arm is arranged substantially at the same distance from the forming means in a vertical direction as the fixed second end of the second arm, so that the pivotable portion of the first arm is longer than the pivotable portion of the second arm.
 18. An apparatus according to claim 14, wherein the fixed pivot point of the arm of each half of the first linkage arrangements and the fixed pivot point of the arm of each half of the third linkage arrangements are arranged substantially at the fixed pivot point of the first arm and the fixed second end of the second arm of each half of the second linkage arrangements in the vertical direction.
 19. A method for sealing a package, which method uses the apparatus according to claim 1, comprising providing the apparatus with forming means comprising a pair of forming flaps, setting the apparatus in a first open package-receiving position, supplying a package to the apparatus, associating each forming flap with a sealing half of at least one pair of reciprocally movable sealing halves, moving the at least one pair of reciprocally movable sealing halves, of the apparatus towards and into contact with the package, pressing two opposing portions of the package towards each other by means of the pair of forming flaps during the movement of the at least one pair of reciprocally movable sealing halves, biasing the at least one pair of sealing halves further by pressing against opposing portions of the package, thereby folding the opposing portions of the package, and sealing the package by supplying energy to the at least one pair of reciprocally movable sealing halves.
 20. A method for sealing a package according to claim 18, further comprising: pivotally attaching each of the forming flaps at a first end to a support, whereby a second end of each of the forming flaps at least partly follows the associated half of the at least one pair of reciprocally movable sealing halves.
 21. A method for sealing a package according to claim 18, further comprising: pivoting the forming flaps from a first essentially vertical position to a second angled position in which the second end is in contact with a portion of each package adjacent an open end thereof.
 22. A method for sealing a package according to claim 20, further comprising: biasing each of the forming flaps, thereby pivoting it into its first essentially vertical position and keeping it in its first essentially vertical position when the associated sealing half of the at least one pair of reciprocically movable sealing halves is in its open position. 